Wrench



UNITED STATES PATENT OFFICE.

G-EO. C. TAFT, OE WORCESTER, MASSACHUSETTS.

WRENCH.

Speccaton of Letters PatentNo. 20,379, dated May 25, 1858.

T o all whom it may concern:

Be it known that I, Geenen C. Tar'r, of ll'orcester, in the county of Worcester and State of Massachusetts, have invented a new and useful or Improved Sciew'-\Vr-encli; and I do hereby declare that the same, is fully described and represented in the following specification and the accompanying drawings, of which- Figure l is a side view, and Fig. 2, a longitudinal section of the wrench.

In such drawings, A denotes the shank of the wrench; B, the movable jaw; C, the fixed or hammer j aw; D, an extension of or proj ection from the jaw B; E, a slider fastened to the said extension and embracing the said shank; L, is the handle and N the holding nut thereof. The part D is provided with a female screw a, to which a male screw F, is adapted and arranged so as to be at the edge of and parallel to the shank A.

Aiiixed to the lower end of the screw, F, is, a worm gear or rosette, G, which is made to screw into a screw rack, H, formed in or on the adjacent edge of the shank, A, and above the ferrule, I, of the handle as shown in the drawings. The directions of the helix threads of the screw, F, and the worm rosette G, are in revers-e of one another, that is, one inclines to the right and the other to the left, one screw being 'a right threaded screw, while the other is what is generally termed a left threaded screw.

The edges of th-e thread of the rosette are milled so as to render it easy for a person to turn the rosette by the application thereto of the thumb of one of his hands when grasping the handle. lVhen the rosette is put in revolution, its screw acting on the rack will move longitudinally either toward the f-errule, I, or the jaw, C, and so as to move the jaw, B, on the shank. At the same time the screw, F, will be put in revolution and by its operation in its female screw a, it will contribute to move the jaw B, and thus by the compound action of the screws, the worm rosette and the rack, the motion of the movable j aw will be accelerated to what it would be, were but one male and one female screw employed.

In order to prevent the threads of the rosette from being forced out of the rack by any great strain tending to force the movable j aw away from the hammer jaw, the rosette is provided with a cylindrical eXtension or slider, K, which projects downward from it, and in line of its axis, and through a cylindrical bearing or hole Z), made through a projectionO, from the collar I. The said parts K and O applied together and to the rosette and ferrule of the handle contribute greatly to strengthen the wrench or prevent it from being injured or broken while in use. The slider, K, also serves to prevent the shank of the screw F, from being bent while the wrench is in use.

In a wrench invented by me, and patented on the 16th of Jun-e 1857, to Henry IV. Mason, my assignee, the male screw of the movable jaw has a male screw extending downward from its nut and working in a female screw made in a projection from the ferrule of the handle. As the nut has no screw cut upon it to work into a rack, the lower screw although it may serve to strengthen the wrench does not perform the function for which I employ the round or cylindrical slider, K, the latter being combined with a worm and a rack (used on the wrench as described) and for the purpose not only of maintaining the thread of the rosette in place in the rack but to strengthen the parts, or prevent breakage of the shank, while the wrench is in use.

The great advantage of my present wrench over that invented by me and patented to Henry IV. Mason, is that, the rosette and screw are combined in one piece, operate in a rack and are arranged between the ferrule projection and the extension of the movable jaw, while the milled screw or rosette in this arrangement causes the strain on the movable jaw to be borne by the shank itself and not by any projection riveted thereto, and the handle by not being subjected to such strain is not liable to be forced off the shank, the further advantage of the bearing of the milled worm against the shank is secured at the same time.

From the above it will be seen that the obj eet of my invention or improvement in a wrench having its movable jaw operated by two reversed male screws is to bring the strain of both the screws directly on the shank and not on either a projection riveted thereto or on a ferrule and wooden handle fixed on the shank; also to prevent the disengagement of the rosette screw from the rack, when the wrench is in use, and furthermore, to prevent the upper screw from being bent as it would be likely to be were such a disengagement to take place.

I do not claim a wrench having its movable j aw operated by two reversed male screws extending in opposite directions either from one another or from a rosette. Nor do I claim a wrench in which the sliding jaw is operated by a single male screw rosette Working in a rack, applied to the stationary jaw. Nor do I claim a wrench having its sliding jaw operated by a single male screw whose milled head enters a recess or notch made in the shank, and has a pivot extending` from it and working in a step made in a projection from the handle such being the construction of the wrench of Doring Goes as patented April 16th, 1841. From this latter, my improved wrench differs materiallyl inasmuch, as it has two reversed, male screws and its rosette instead of being stationary in other respects than being capable of being revolved, will move endwise with the screws, when they revolve. Furthermore, my improved wrench has the cylindrical slider K so made as not only to revolve with the male screws but move endwise with them and perform the function of maintaining the male screw rosette in connection with its screw rack at whatever distance the rosette may be from the projection, O. No such slider is found in Goes wrench, because, it is not necessary there for in such there is no endwise movement. of the screw, and no worm rosette and rack, to be maintained in connection. Goes uses a pivot working in a cup or step and both are so formed that no endwise motion of the pivot can take place. But

Vhat I claim in a wrench provided with twoV reversed male screws for operating its movable jaw, is

Arranging the lowermostscrew, G, to work in a screw rack, H, on the shank, A, oit the wrench and providing the said screw with a cylindrical slider, K, extending below it and operating so as not only to turn around but move longitudinally with the screw and in a socket piece, G, connected with the handle, the whole being substantially as described.

In testimony whereof I have hereunto set my signature this thirtieth day of October,

GEO. G. TAFT. IVitnesses JAMES I-I. BANoRoFT, JOHN GOULDING. 

